Power valve for limiting torque of plunger pump
By employing a valve sleeve, valve core, multiple oil chambers, and sealing structure in the plunger pump torque limiter, the problems of high processing difficulty and significant temperature influence in the prior art are solved, achieving high precision and reliability in torque control and protecting the normal operation of the engine.
Patent Information
- Application Number
- CN202520111044.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-17
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-01-17
AI Technical Summary
Existing plunger pump torque limiters are difficult to manufacture and are greatly affected by temperature, making them unable to effectively protect the engine from overshoot and stalling.
A power valve comprising a valve sleeve, a valve core, a valve body, and first and second elastic structures is designed. By setting steps of different diameters and multiple oil chambers on the valve core, torque is controlled by hydraulic pressure. Sealing rings and protective structures are set in key parts to prevent external contaminants from entering, simplifying processing and reducing the impact of temperature.
It achieves a simple structure, low processing difficulty, minimal temperature influence, high torque control accuracy, prevents dust and water vapor from entering, ensures normal operation of the power valve, and protects the engine from overshoot and stall.
Smart Images
Figure CN223724771U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a power valve for limiting plunger pump torque belongs to hydraulic pump technical field. BACKGROUND
[0002] In the hydraulic system with swash plate type axial plunger pump, it is usually needed to reliably limit the torque of plunger pump by torque limiter, i. e. power valve, to protect the engine from the torque of plunger pump to rotate speed and even stall, and the existing plunger pump torque limiter has some defects: high processing difficulty, big temperature influence on performance, etc. SUMMARY
[0003] In view of the defects of the prior art, the utility model discloses a power valve for limiting plunger pump torque with low processing difficulty and small temperature influence.
[0004] To achieve the foregoing utility model purposes, the utility model adopts the technical scheme of comprising:
[0005] A power valve for limiting plunger pump torque, comprising a valve sleeve, a valve core, a valve body, a first elastic structure and a second elastic structure, the valve sleeve is provided with a drain cavity, a control oil cavity and a high-pressure oil cavity, the valve core is located in the interior of the valve sleeve, the valve core comprises a core shaft, the core shaft is provided with a first step, a second step and a third step, the diameter of the first step is smaller than that of the third step, the second step corresponds to the position of the control oil cavity, and the second step blocks the control oil cavity; high-pressure oil enters the high-pressure oil cavity, and under the drive of hydraulic pressure, the valve core moves along the axial direction of the valve sleeve, the second step is staggered with the control oil cavity, the high-pressure oil cavity and the control oil cavity are communicated, so that the high-pressure oil enters the control oil cavity from the high-pressure oil cavity; the valve sleeve and the valve core are arranged in the interior of the valve body; the first elastic structure is arranged in the interior of the valve body and the first elastic structure is arranged at one end of the valve core, and the first elastic structure is used at least for balancing the hydraulic pressure generated in the movement process of the valve core; the second elastic structure is arranged in the interior of the valve body and the second elastic structure is arranged at the end of the valve core away from the first elastic structure, and the second elastic structure is used at least for pushing the valve sleeve to reset.
[0006] Further, the first elastic structure comprises a first spring seat, a first spring and a second spring, the first spring and the second spring are both sleeved on the first spring seat, the first spring seat is arranged at one end of the valve core, the first spring and the second spring are used at least for balancing the hydraulic pressure generated in the movement process of the valve core, and the first spring is arranged in the interior of the second spring.
[0007] Further, the second elastic structure comprises a second spring seat arranged at one end of the valve core away from the first spring seat, and a return spring is arranged on the second spring seat, and the return spring is used at least for pushing the valve sleeve to return.
[0008] Further, an adjusting screw sleeve is arranged inside the valve body, one end of the second spring is in contact with the adjusting screw sleeve, and the other end is in contact with the first spring seat, and the adjusting screw sleeve is used at least for adjusting the spring force of the second spring.
[0009] Further, a fastener for fixing the adjusting screw sleeve is arranged on one side of the adjusting screw sleeve.
[0010] Further, an adjusting screw rod is arranged inside the adjusting screw sleeve, one end of the adjusting screw rod is in contact with one end of the first spring, and the adjusting screw rod is used at least for adjusting the spring force of the first spring, and a locking nut is arranged on the outside of the adjusting screw rod, and the locking nut is used at least for fixing the adjusting screw rod.
[0011] Further, a protective cap is arranged on the outside of the adjusting screw rod, and the two ends of the locking nut are in contact with the protective cap and the adjusting screw sleeve respectively.
[0012] Further, a first sealing ring is arranged between the protective cap and the locking nut.
[0013] Further, a screw plug is arranged on the outside of the return spring, and the screw plug is connected with the valve body.
[0014] Further, a second sealing ring is arranged between the valve body and the screw plug.
[0015] Further, a fourth step is arranged on the core shaft, and the fourth step is arranged between the first step and the third step.
[0016] Compared with the prior art, the advantages of the utility model include:
[0017] 1) the utility model provides a power valve for limiting the torque of a plunger pump, three oil chambers are arranged on the valve sleeve, steps with different diameters are arranged on the core shaft, hydraulic pressure is generated due to the area difference of the steps on the core shaft after high-pressure oil enters the high-pressure oil chamber, the valve core is pushed to move, so that the high-pressure oil enters the control oil chamber, power control is realized, and the torque is controlled.
[0018] 2) the utility model provides a power valve for limiting the torque of a plunger pump, a protective cap is arranged on the outside of the adjusting screw rod, and a sealing ring is arranged between the protective cap and the locking nut, which is used for sealing the adjusting screw rod, preventing external dust, water vapor and the like from entering the valve body, and preventing the normal work of the power valve from being affected.
[0019] 3) The utility model provides a power valve for limiting plunger pump torque, set up the screw plug outside reset spring, and set up sealing ring between valve body and screw plug, for is inside valve body is in sealed state, prevent dust, water vapor etc. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical scheme in the embodiment of the present application or prior art, the following will briefly introduce the drawing needed to be used in the embodiment or prior art description, obviously, the drawing in the following description is only some embodiments in the present application, for ordinary skilled person in the art, under the premise of not paying creative labor, other drawings can also be obtained according to these drawings.
[0021] Figure 1 It is the whole structure schematic diagram of a power valve for limiting plunger pump torque in a typical embodiment case of the utility model,
[0022] Figure 2 It is the structure schematic diagram of valve sleeve provided in a typical embodiment case of the utility model,
[0023] Figure 3 It is the structure schematic diagram of valve core provided in a typical embodiment case of the utility model,
[0024] Reference signs: 1, oil discharge cavity, 2, control oil cavity, 3, high pressure oil cavity, 6, protective cap, 7, locking nut, 8, adjusting screw, 9, first spring, 10, second spring, 11, first spring seat, 12, valve sleeve, 13, second spring seat, 14, reset spring, 15, second sealing ring, 16, screw plug, 18, valve core, 20, nut, 21, adjusting screw sleeve, 22, first sealing ring, 23, first step, 24, second step, 25, third step, 26, fourth step, 27, core shaft. DETAILED DESCRIPTION
[0025] In view of the deficiencies in the prior art, the present application has been long-term research and a large number of practices, and the technical scheme of the utility model is obtained. The technical scheme, its implementation process and principles will be further explained as follows.
[0026] As Figure 1 , Figure 2 , Figure 3The utility model discloses a power valve for limiting plunger pump torque, which comprises a valve sleeve 12, a valve core 18, a valve body, a first elastic structure and a second elastic structure, wherein the valve sleeve 12 and the valve core 18 are arranged inside the valve body; the valve sleeve 12 is provided with an oil leakage cavity 1, a control oil cavity 2 and a high-pressure oil cavity 3; the valve core 18 is located inside the valve sleeve 12; the valve core comprises a core shaft, which is provided with a first step 23, a second step 24 and a third step 25; the diameter of the first step 23 is smaller than that of the third step 25; the second step 24 corresponds to the position of the control oil cavity and blocks the control oil cavity; high-pressure oil enters the high-pressure oil cavity and moves the valve core 18 along the axial direction of the valve sleeve 12 under the drive of hydraulic pressure; the second step 24 is staggered with the control oil cavity; the high-pressure oil cavity 3 and the control oil cavity 2 are communicated to allow the high-pressure oil to enter the control oil cavity 2 from the high-pressure oil cavity 3. In the initial state, the second step 24 blocks the control oil cavity.
[0027] In one embodiment, the diameter of the first step 23 is 5 cm, and the diameter of the third step 25 is 5.3 cm; the two steps have an area difference, so that the valve core is pushed by the hydraulic pressure after the high-pressure oil enters the high-pressure oil cavity; according to the formula F=p*s, F is the hydraulic pressure, P is the pressure, and S is the area difference, i.e. F=P*(π*5.3*5.3 / 4-π*5*5 / 4). Therefore, the generated hydraulic pressure is balanced with the left first elastic structure to control the torque.
[0028] When the power valve works, high-pressure oil enters the high-pressure oil cavity 3; due to the area difference between the two steps at the ends of the core shaft, the hydraulic pressure that moves the valve core 18 to the left is generated, so that it is balanced with the first elastic structure; at this time, the second step 24 is staggered with the control cavity 2, the high-pressure oil cavity 3 and the control cavity are communicated, and the high-pressure oil at the high-pressure oil cavity 3 enters the control cavity 2 due to the opening of the valve core 18, thereby changing the displacement of the pump and playing a power control role.
[0029] In the present application, three oil cavities are arranged on the valve sleeve 12, and steps with different diameters are arranged on the core shaft; after the high-pressure oil enters the high-pressure oil cavity, the hydraulic pressure is generated due to the area difference between the steps on the core shaft, which pushes the valve core to move and allows the high-pressure oil to enter the control oil cavity, thereby realizing power control and controlling the torque. Compared with the traditional power valve, the structure of the present application is simple, the processing difficulty is low, the temperature influence is small, and the torque control precision is high.
[0030] The first elastic structure is arranged inside the valve body and at one end of the valve core 18, and is used at least for balancing the hydraulic pressure generated during movement of the valve core 18; specifically, the first elastic structure comprises a first spring seat 11, a first spring 9 and a second spring 10, the first spring 9 and the second spring 10 are both arranged on the first spring seat 11, the first spring seat 11 is arranged at one end of the valve core 18, the first spring 9 and the second spring 10 are used at least for balancing the hydraulic pressure generated during movement of the valve core 18, and the first spring 9 is arranged inside the second spring 10.
[0031] The second elastic structure is arranged inside the valve body and at one end of the valve core 18 away from the first elastic structure, and is used at least for pushing the valve sleeve 12 to reset. Specifically, the second elastic structure comprises a second spring seat 13 arranged at one end of the valve core 18 away from the first spring seat 11, and a reset spring 14 arranged on the second spring seat 13, the reset spring 14 is used at least for pushing the valve sleeve 12 to reset.
[0032] On the basis of the above, in order to adjust the spring force of the second spring 10, an adjusting screw sleeve 21 is arranged inside the valve body, one end of the second spring 10 is in contact with the adjusting screw sleeve 21, and the other end is in contact with the first spring seat 11, in order to fix the adjusting screw sleeve 21, a fastener is arranged on one side of the adjusting screw sleeve 21, the fastener can comprise a nut or a buckle structure, and in the embodiment, the fastener comprises a locking nut.
[0033] On the basis of the above, in order to adjust the spring force of the first spring 9, an adjusting screw rod 8 is arranged inside the adjusting screw sleeve 21, one end of the adjusting screw rod 8 is in contact with one end of the first spring 9, and the outer side of the adjusting screw rod 8 is provided with a locking nut 7, the locking nut 7 is used at least for fixing the adjusting screw rod 8.
[0034] In some embodiments, in order to protect the adjusting screw rod 8, a protective cap 6 is arranged on the outer side of the adjusting screw rod 8, and the two ends of the locking nut 7 are respectively in contact with the protective cap 6 and the adjusting screw sleeve 21.
[0035] Preferably, in order to better protect the adjusting screw rod 8 and prevent dust, water vapor and the like from entering the inside of the valve body, a first sealing ring 22 is arranged between the protective cap 6 and the locking nut 7.
[0036] In some embodiments, in order to seal the reset spring 14, a screw plug 16 is arranged on the outer side of the reset spring 14, the screw plug 16 is connected with the valve body, and preferably, a second sealing ring 15 is arranged between the valve body and the screw plug 16.
[0037] In some embodiments, a fourth step 26 is provided on the mandrel, the fourth step 26 being provided between the first step 23 and the third step, the fourth step 26 acting as a support, the fourth step 26 having a gap for the passage of high pressure oil.
[0038] It should be understood that the above embodiments are only to illustrate the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made in accordance with the spirit and essence of the present application shall be covered within the protection scope of the present application.
Claims
1. A power valve for limiting plunger pump torque, characterized by: The utility model relates to a valve sleeve (12) is provided with oil leakage cavity (1), control oil cavity (2) and high pressure oil cavity (3), Valve core (18) is located inside valve sleeve (12), and the valve core includes shaft (27), is provided with first step (23), second step (24) and third step (25) on the shaft, the diameter of first step (23) is less than the diameter of third step (25), second step (24) corresponds with control oil cavity (2) position, and second step (24) blocks control oil cavity (2);High pressure oil enters high pressure oil cavity, and under the drive of hydraulic pressure, valve core (18) moves along the axial direction of valve sleeve (12), and second step is staggered control oil cavity, and high pressure oil cavity (3) and control oil cavity (2) are communicated to make high pressure oil from high pressure oil cavity (3) into control oil cavity (2); Valve body, valve sleeve (12) and valve core (18) are arranged in the valve body, First elastic structure is arranged in the valve body, and the first elastic structure is arranged at one end of the valve core (18), and the first elastic structure is at least used to balance the hydraulic pressure generated in the movement of the valve core (18); Second elastic structure is arranged in the valve body, and the second elastic structure is arranged at the end of the valve core (18) away from the first elastic structure, and the second elastic structure is at least used to push the valve sleeve (12) to reset. The first elastic structure includes a first spring seat (11), a first spring (9) and a second spring (10), the first spring (9) and the second spring (10) are sleeved on the first spring seat (11), the first spring seat (11) is arranged at one end of the valve core (18), the first spring (9) and the second spring (10) are at least used to balance the hydraulic pressure generated in the movement of the valve core (18), and the first spring (9) is arranged in the second spring (10).
2. A power valve for limiting the torque of a plunger pump according to claim 1, characterized in that: The second elastic structure includes a second spring seat (13), the second spring seat (13) is arranged at the end of the valve core (18) away from the first spring seat (11), a reset spring (14) is arranged on the second spring seat (13), and the reset spring (14) is at least used to push the valve sleeve (12) to reset.
3. A power valve for limiting the torque of a plunger pump according to claim 1, characterized in that: An adjusting screw (21) is arranged in the valve body, one end of the second spring (10) is in contact with the adjusting screw (21), and the other end is in contact with the first spring seat (11); the adjusting screw (21) is at least used to adjust the spring force of the second spring (10).
4. A power valve for limiting the torque of a plunger pump according to claim 2, characterized in that: A fastener is arranged on one side of the adjusting screw (21) for fixing the adjusting screw (21).
5. A power valve for use in limiting the torque of a plunger pump as defined in claim 4, wherein: An adjusting screw rod (8) is arranged in the adjusting screw (21), one end of the adjusting screw rod (8) is in contact with one end of the first spring (9), the adjusting screw rod (8) is at least used to adjust the spring force of the first spring (9), and a locking nut (7) is arranged on the outer side of the adjusting screw rod (8), and the locking nut (7) is at least used to fix the adjusting screw rod (8).
6. A power valve for limiting the torque of a plunger pump as defined in claim 4, wherein: 7. A power valve for use in limiting the torque of a plunger pump as defined in claim 6 wherein: The outer side of the adjusting screw (8) is provided with a protective cap, and the two ends of the locking nut (7) are respectively in contact with the protective cap and the adjusting screw sleeve (21).
8. A power valve for limiting the torque of a plunger pump according to claim 7, characterized in that: A first sealing ring (22) is arranged between the protective cap and the locking nut (7).
9. A power valve for use in limiting the torque of a plunger pump as defined in claim 3 wherein: The outer side of the reset spring (14) is provided with a screw plug (16), and the screw plug (16) is connected with the valve body. And / or, a second sealing ring (15) is arranged between the valve body and the screw plug (16).
10. A power valve for limiting the torque of a plunger pump according to claim 1, wherein: A fourth step (26) is arranged on the mandrel, and the fourth step (26) is arranged between the first step (23) and the third step (25).